Websites are web1 (skyflashdemo.biz) and web2 (skyflash.it). Every site has 3 daily backups configured. Every website has its own ftp user

When i connect as user via FTP, i can browse the entire website directory and any subfolder as stats, log, cgi-bin etc, but i obtain this message when i try to browse the backup symlink: Can't open backup: Permission denied